From 9abbf426bf6e56ad92ab66fd756b9ca7c8d738ec Mon Sep 17 00:00:00 2001
From: Marco Allegretti <marco@karapace.dev>
Date: Tue, 24 Feb 2026 11:46:51 +0100
Subject: [PATCH] cli: exit cleanly on broken pipe

Piping CLI output into tools like head may close stdout early.
Rust then panics when printing.

Install a panic hook that exits successfully on EPIPE instead of
emitting a panic backtrace.
---
 crates/karapace-cli/src/main.rs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/crates/karapace-cli/src/main.rs b/crates/karapace-cli/src/main.rs
index 8138048..8e953e5 100644
--- a/crates/karapace-cli/src/main.rs
+++ b/crates/karapace-cli/src/main.rs
@@ -212,6 +212,19 @@ enum Commands {
 
 #[allow(clippy::too_many_lines)]
 fn main() -> ExitCode {
+    let default_hook = std::panic::take_hook();
+    std::panic::set_hook(Box::new(move |info| {
+        let msg = info.to_string();
+        if msg.contains("Broken pipe")
+            || msg.contains("broken pipe")
+            || msg.contains("os error 32")
+            || msg.contains("failed printing to stdout")
+        {
+            std::process::exit(0);
+        }
+        default_hook(info);
+    }));
+
     let cli = Cli::parse();
 
     let default_level = if cli.trace {